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127 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Levels of Organization |
- Bone Cells - Bone Tissue - Bones/Organs - Skeletal System |
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Bone Cells |
Osteocytes |
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Bone Tissue |
- Osseous Tissue aka Connective Tissue - Matrix = Osteoid + Inorganic Salts |
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Bones/Organs |
- Organs with Osseous tissue, connective tissue, smooth muscle, nerve tissue - CLassified by structure, formation, and shape |
types of tissues and how classified |
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Skeletal System |
- Bones - Cartilage - Ligaments - Joints - Bone marrow |
What makes it up? 5 BCLJB |
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Functions of Skeletal System |
- Support: supports soft tissues, place to attach muscles - Protection: Skull, vertebrae, ribs & sternum, hipbones (Repro Organs) - Assist in movement: movement requires contracting muscles & points of attachment to bone - Mineral Storage & Release: calcium & phosphate, available on demand - Blood Cell Production: called hemopoiesis, in red marrow - Storage of energy: lipids are stored in yellow marrow - Repair & remodel: bone tissue is constantly being broken down & rebuilt |
SPAMBRS (7) |
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Cartilage Basic Characteristics |
- Gelatinous Connective Tissues - Matrix semisolid and have no mobility - Strength is from fibers (collagen) - Resiliency from GAGs - Avascular, all nutrients diffuse faster than capillary beds can be grown |
GRAMS |
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Cartilage General Structure |
- Cells: Chondrocytes (modified fibroblasts) live in spaces called lacunae - Matrix is semisolid: full of collagen & GAGs, mostly chondroitin sulfate which is rubbery - Perichondrium: External membrane, dense Irregular |
CMP |
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Types of Cartilage |
- Hyaline - Elastic - Fibrocartilage |
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Hyaline |
- Means glassy which describes appearance of matrix - Most wide spread, strong and resilient - destined to become bone - makes up embryonic skeleton - Forms costal cartilages of ribs, rings of trachea, articular cartilage, nasal septum |
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Elastic Cartilage |
- Less collagen, more elastic fibers - Exterior of ear, epiglottis |
Made of, location |
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Fibrocartilage |
- Maximum strength with limited flexibility - Looks like dense Connective Tissue but chondrocytes are in lacunae - Pubic symphysis, intervertebral discs, menisci |
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General Characteristics of Bone Tissue |
- Ground Substance: solid= ECF + GAGs + Calcium carbonate & calcium phophate salts - Cells: Osteoprogenitor, osteoblasts, osteocytes, osteoclasts - Fibers: Collagen - Strong and lightweight: strongest of the connective tissues - Dynamic: bone is continually being broken down & reformed - Highly structure: organized as osteons - Vascular: unlike cartilage, bone is highly vascular & innervated |
7. GCFSDHV |
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Classification of Bones |
- shape: long, flat, irregular, short - Structure: compact bone, spongy bone - Origin: Membranous bone, endochondral bone |
3 sso |
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Compact Bone |
- Laid down in lamellar (laminated) sheets in successive layers - Concentric ring structure - amount proportional to amount of stress - Forms outer layer of all bone & bulk of body of long bones |
describe 4 |
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Spongy Bones |
- Bone is laid down in struts/forms a latticework=trabeculae - Built in triangles - Found at ends of long bones, center of other bones |
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Membranous Bone |
- This bone is formed directly in membrane - does not go through a stage of cartilage - includes flat bones of skull, mandible and clavicle |
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Endochondral Bone |
- Develops from hyaline cartilage - Most bones form from hyaline cartilage and hyaline cartilage always becomes bone |
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Osteoprogenitor |
-Unspecialized - capable of mitosis - defferentiate into osteoblasts - found in periostem, endosteum, canals |
3 + where found |
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Osteoblasts |
- Large granular cells - cant undergo mitosis - found on surface of bone - form bone - secrete the osteoid: collagen, proteoglycans, and glycoproteins |
description and what they secrete |
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Osteocytes |
- as blasts surround themselves with matrix - mature bone cells - maintain matrix, and exchange nutrients/wastes with blood - found in lacunae |
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Osteo Clasts |
- Phagocytic cells that reabsorb bone - may develop from monocytes - functions include reabsorption for development, growth, maintenance, repair of bone, and maintenance of blood calcium - cells secrete organic acids to break down minerals, lysosomes enzymes break down collagen |
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Fiber |
- Collagen is the fiber of bone extracellular matrix - most abundant protein in your body - Function: holds you together |
Resists, transfers pressures, tensions due to muscle contractions, and gravity |
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Matrix |
- Organic: secreted by osteoblasts - Osteoid: Collagen, GAGs (Proteoglycans), osteonectins (Glycoproteins, bind GAGs & salts together) - Inorganic: calcium phosphate= hydroxyapatite & calcium carbonate |
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Architecture of bone tissues |
- Bone is for support: must be rigid & strong - but not heavy - Bone is very metabolic for constant repair - needs good blood supply - Lamellar construction, with canals or trabeculae for blood supply - use of both compact and spongy bone |
represents compromise between stability and mobility |
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Compact Bone |
- Laid down in lamellar sheets, successive layer - Concentric ring structure - form outer layer of all bone & diaphysis of long bone - Proportional to amount of stress put on bone - Structural unit of bone is osteon, pillar - Center is central canal, which contains blood & liymp vessels, nerve - Concentric lamellae=rings of calcified matrix - lacunae contain osteocytes - perforating canals: bring blood vessels from medullary cavity, periosteum - Osteons orient in direction of force |
detailed description. name eveyrhing |
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Direction of force on osteons cause these patterns |
Concentric, interstitial, and circumferential lamella |
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Compact Bone Function |
- Design is very strong - Long bones: support weight of body - Withstands great force from one direction, parallel to osteons - bone does not break when force is applied to either end - can break if enough force is applied to side |
Explain design |
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Spongy Bone |
- Lamellar, no osteons, basic unit= trabeculae - Osteocytes live in lacunae - Caniliculi are open to rich blood supply of red marrow - outside of trabeculae is covered w/ endosteum, includes osteoblasts and osteocytes - Laid down in struts/ latticework of trabeculae - lightens bone, makes it more moveable - Trabeculae built in triangles to withstand stress from many directions - found at ends of long bones, center of others - Spaces filled w/ red marrow: reticular cells, stem cells, capillaries |
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Important structures of bone |
- Epiphysis: provides for articulation & muscle attachment - Diaphysis: shaft of bone, contains nutrient foramen - Metaphysis: between diaphysis & epiphysis; which includes epiphysial plate which is a layer of hyaline cartilage which allows for bone growth |
Gross anatomy of long bone. EDM |
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Articular cartilage |
- Reduces friction & absorbs shock at moveable joints - formed of hyaline cartilage which can compress and spring back - Semi-solid cartilage, holds water via GAGs and acts as hydraulic shock absorber - at moveable joints, articulation is cartilage to cartilage |
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Periosteum |
- Connective tissue on outside of bone - outer fibrous layer is dense irregular connective tissue with blood & lymph vessels, nerves - inner osteogenic layer: elastic fibers and bone cells |
Growth anatomy of long bone |
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Periosteum function |
- essential for bone growth, repair & nutrition - point of attachment for tendons & ligament - Connective tissue structures are firmly attached by sharpey's fibers |
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Sharpey's Fibers |
Collagen fibers which penetrate cortical bone |
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Medullary Cavity (Marrow Cavity) |
- space within diaphysis - yellow marrow in adults - site of lipid storage: fuel reserve |
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Endosteum |
- Lines medullary cavity - covers trabeculae - contains osteoprogenitor cells & osteoclasts |
Gross anatomy |
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Red bone Marrow |
- fills all bone cavities in early life - after puberty limited to spongy bone of ribs, sternum, hip, ends of long bones - hemopoietic tissue contains stem cells - highly mitotic, undifferentiated cells which give rise to all RBCs & WBCs |
Gross anatomy long bone |
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Immature Bone |
- woven - Collagen fibers are woven as in dense irregular connective tissue |
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Mature Bone |
-Lamellar construction - collagen forms a gridwork; can be compact or spongy |
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Ossification |
- Formation of bone - includes: intramembranous, endochondral ossification, and sesamoid bone |
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Intramembranous |
- develops in membrane - mesenchyme of fibrous connective tissue - Steps: osteoblasts differentiate, cluster together & secrete osteoid, matrix mineralizes or calcifies, cells become trapped & differentiate into osteocytes - location: flat skull bones, mandible, clavicle |
Include location and steps 5 |
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Endochondral Ossification |
- Bone develops in cartilage - pattern laid down in cartilage - Shape in response to conditions at the site where needed - cells in perichondrium differentiat into osteoblasts - Bone laid down in a collar around the shaft which kills chondrocytes since nutrients can no longer diffuse inwards - Blood vessels & osteoblasts invade cartilage, degrade it and build bone - bone fills in the shaft area, then spreads upwards - Center of shaft is hollowed by osteoclasts |
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Sesamoid Bone |
- develops inside tendons in response to wear -gives angles of attack to tendon - provides mechanical advantage |
Best example is patella, found at base of thumb & big toe |
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Growth of long bone: Length |
- Epiphysial plate: layer of hyaline cartilage in metaphysis, from endochondral ossification - Cartilage cells prodcued by mitosis on epiphysial side of plate - old cartilage destroyed & replaced by bone on diaphysial side of plate - More bone in diaphysis, epiphysial plate remains same size, and bone grows -eventually bone replaces all cartilage, epiphysial line remains, happens at puberty |
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Growth of Long Bone: Diameter |
-Osteoclasts destroy bone lining medullary cavity=larger cavity - Osteoblasts from periostium add new bone to outer surface |
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Bone repair & remodeling |
- Happens all the time, continually renews - Remodeled & redistributed along lines of stress -Weight bearing exercise encourages process - 5% is under reconstruction at any time - daily wear produces small cracks or stress fractures - repaired by bone formation/resorption - during growth: bone formation exceeds bone resorption - aging= osteoporosis - Requires minerals (Calcium & Phosphate), Vitamins (A,C,D), and Hormones (GH, calcitonin, PTH) (Sex steroids inhibit) |
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Fracture Repair |
-Blood clot (Hematoma) - Granulation tissue - Fibrous Connective Tissue - Hyaline Cartilage - Woven Bone - Lamellar bone |
6 steps |
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Joints or articulations |
-Exist wherever 2 supporting connective tissues meet - can be between bone & bone, bone & cartilage, cartilage & cartilage - w/out joint would be no movement - provide mobility - also immobile joints that provide protection |
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Classification of joints |
-Structure: fibrous, cartilaginous, synovial -Function: synarthrosis, amphiarthrosis, diarthrosis |
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Fibrous Joints |
- no joint cavity, no synovial cavity - bones held very close together by fibrous connective tissue |
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Types of Fibrous Joints |
- Sutures (seam) - Syndesmosis - Gomphosis |
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Sutures |
- Joint is thin layer of dense fibrous connective tissue & interdigitated bone - bone not united initially because of development - allows change in shape of head during birth |
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Syndesmosis |
- Joint has more fibrous connective tissue - forms an interosseous membrane or ligament - Permists slight movement |
examples include distal articulation of tibia & fibula |
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Gomphosis |
- Joined by fibrous connective tissue & special tissue cement |
only found in teeth in their body sockets |
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Synostosis |
- Complete fusion of bone occurs across suture lines - sutures become joined by bone |
frontal bone, os coxae, sacrum |
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Cartilaginous Joints |
- articulating bones tightly joined by cartilage - permit little or no movement more than fibrous joints |
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Types of cartilaginous joints |
- Synchondrosis -Symphysis |
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Synchondrosis |
- connecting material is hyaline cartilage - Epiphysial plate is temporary joint of growth |
#1 rib/sternum joint, and costochondral joints are other examples of synchondroses |
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Symphasis |
- Connecting material is broad, flat discs of fibrocartilage - 2 bones have hyaline cartilage on bony surfaces - fibrocartilage disc between the surfaces |
Intervertebral discs, pubic symphasis |
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Synovial Joint |
- All have hyaline cartilage covering the articulating bones - Joint cavity -Moveable joint & favors mobility - contains; synovial cavity, synovial fluid, synovial membrane, articular cartilage, articular joint capsule |
Examples of large: knee, shoulder, hip Example of small: ear ossicles |
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Synovial Cavity |
- space between articulating bones - keeps them from touching - space well defined at rest - occluded with loading |
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Synovial Fluid |
- produced by synovial membrane - filtrate of blood - thick & viscous - serves as lubricant for joints, to reduce friction from movement - Shock absorber - Nourishes chondrocytes -cartilage sponges up this fluid at rest - weeps back out when joint is loaded=weeping lubrication |
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Synovial Membrane |
- Composed of areolar connective tissue w/ elastic fibers & adipose tissue - primarily fibroblasts, which add GAGs & macrophages - Highly vascularized & has mast cells - potential for histamine release & inflammation due to vascularity - also found in bursa & tendon sheaths |
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Articular Cartilage |
- covering the bones is hyaline - bone never touches bone - because hyaline becomes bone, arthritis is a given if you live long enough |
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Articular (joint) capsule |
-Encloses synovial cavity - Unites articulating bones - Outer layer= fibrous capsule, made of dense irregular connective tissue - attaches periosteum -flexible to allow movement, strong to resist dislocation - Inner layer= synovial membrane |
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Acessory Structure of synovial Joints |
- Ligaments - Tendons - Bursa - Synovial tendon sheaths -cartilage pads or fibrocartilage discs |
LTBSC |
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Ligaments |
- bands of white fiber connective tissue - Join bone to bone - hold bones in place - stabilize joints - prevent excessive or abnormal ranges or angles of movement - 3 categories; extrinsic, intrinsic, capsular - often damaged in athletic events -Treatment is RICE: prevents swelling due to histamine release |
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3 categories of ligament |
- Extrinsic: outside joint capsule, runs parallel to long axis of bone, prevents lateral instability. e.g. collateral ligament in knee - Intrinsic: runs w/in synovial membrane, prevent over extension, criss-cross inside joint. e.g. Cruciate in knee - Capsular: bands of white fibrous connective tissue in joint capsule, reinforces the synovial membrane |
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Tendons |
- cross joints & connect muscle to bone - muscle is pulling on bone to produce muscle tone & movement - tendons give strenght & stability to joints |
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Bursa |
- synovial sacs filled w/fluid: acts like pillow to cushion structures and helps avoid abrasion - strategically situated to alleviate friction in some joints - lovated between skin & bone, tendon & bone, muscle & bone, ligament & bone - resemble joint capsule - Walls made of fibrous CT, lined w/ synovial membrane and filled w/ synovial fluid - complex joints w/ lots of ROM have many bursae |
eg knee, shoulder, elbow |
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Synovial Tendon Sheaths |
-found where thin rope-like tendons run over bony surfaces - tendon will run in a long synovial tunnel - Outer layer: periosteum - Inner Layer: synovial membrane & tendon is bathed in synovial fluid - Is essentially bursa wrapped around tendon |
Hands, feet |
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Cartilage pads & fibrocartilage discs |
-Improve fit between articulating bones & helps to make joint more stable - Divides synovial cavity - Makes bone association more intemate w/out losing flexibility |
found in TemporoMandibular joint & knees medial and lateral meniscus |
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Selected Joints: Hip |
- Very stabledue to shape of articulating bones - Manye Ligaments - Deep socket and Ball - Large Muscles - Strong Capsule |
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Selected Joints: Knee |
-not deep socket that would interfere w/ proper cushioning - tempt injurty by setting rigid limits on joint movement - side-side movement limited by external ligaments; medial & lateral collateral ligaments -anterior/posterior slippage is controlled by anterior & posterior cruciate ligaments - joins is cushioned by cartilage pads=meniscus cartilage - major stabilizer of this joint is quadraceps muscle & tendon w/ patella inside |
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Selected joint: Shoulder |
- great tendon sheath for biceps brachii, - tendon is major stabilizer |
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Selected Joints: Vertebrae |
- intervertebral disc: cartilaginous joint, symphysis, made of fibrocartilage - allows only a small amount of mobility/flexibility - all together give tremendous flexibility & movement |
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Selected Joint: Intervertebral discs |
- spacing elements, make vertebra more flexible - lie between vertebrae - account for 1/4 lenght of vertebral column -shrink with age and we lose height - annulus fibrosus: outer part of disc, concentric rings of fibrocartilage - nucleus pulposus: inner portion, cavity filled w/ soft mucus like gel that acts as a shock absorber w/impact, disc compresses & fluid spreads out |
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Factors that aid strenght and limit mobility in synovial joints |
- shape of articulating bones: ball & socket is very stable - Strenght & tension of ligaments: direct movement, prevent undesirable movement - arrangement & tension of tendons/muscles: most important facto in stability - articular capsule: strengthens joint, prevents bones being pulled apart - apposition of other tissues |
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Factors that solve mobility problems in synovial joints |
-synovial fluid: acts like a lubricant -synovial fluid, bursa & synovial tendon sheaths: reduce friction - intervertebral discs, articular discs, cartilage & synovial fluid: act as shock absorbers |
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Flexion and extension |
- Flexion: decrease angle between bones - Extension: increase angle between bones |
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abduction and adduction |
-abduction: move away from midline -adduction: move towards midline |
adduction = adding |
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Circumduction |
limb moves in circle |
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Rotation |
Turn bone around its own long axis medial & lateral |
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Gliding |
vertebrae, intercarpal, intertarsal |
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Elevation and depression |
shoulder and mandible |
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Protraction and retraction |
shoulder, and mandible |
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Supination and pronation |
radius & ulna |
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Inversion & eversion |
foot and ankle |
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Types of synovial joints |
-Gliding: ribs & vertebrae -Hinge: knee, elbow, ankle -pivot: ulna/radius, axis/atlas -saddle: trapezium of the carpus & metacarpal of thumb -ball & socket: shoulder & hip |
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Muscle Tissue |
- contractile - highly metabolic - vascular - neural - all contractile tissues: skeletal, cardiac and smooth |
5 CHVN all |
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Muscular system |
-refers to skeletal muscle system - includes muscle tissue & connective tissue that forms individual muscle organs |
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Myo & sarco, osteo and chondro |
Myo & sarco= prefix for muscle osteo= bone chondro=cartilage |
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Characteristics of Muscle Tissue |
- Contractility: muscle can shorten & thicken - excitability: muscle tissue responds to neurotransmitters producing action potential -Extensibility:muscle can be extended w/out damaging tissue -elasticity: muscle returns to original shape after contraction or stretching |
4 CEEE |
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Function of Muscle Tissue |
- Motion: relies on integrated function of bones, joints, & muscle -Movement of substances within body: heart, vessels, GI, Urine, Sperm,ova -Maintenance of posture: stabilize body position - heat production: working muscles convert 75% E to heat, only 25% to motion -Guard: entrances/exits |
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Morphology of muscle tissue |
Striated: myofibrils are aranged in bands Smooth: myofribrils are present but bands do not show in light microscope |
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Function of muscle tissue |
Voluntary: consciously regulated Involuntary: regulation is not conscious, achieved via nerves & hormones |
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Three muscle types |
-Skeletal: striated,voluntary; attached to bone, fascia, other muscle -Cardiac:striated, involuntary; heart muscle; has pacemaker system -smooth:unstiate, usually involuntary; part of many hollow internal organs and skin |
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Cardia Muscle Tissue |
-only found in heart and is principal tissue in heart wall - striated and involuntary -Control: displays autorhythmicity -Fibers are branching: have only one centrally located nucleus with many mitochondria -cells connected to each other by intercalated discs -discs are interdigitation of cell membranes -discs contain anchoring junction & gap junctions -Syncytium= group of interconnected muscle cells that function mechanically & electrically as a unit -Two kinds of cardiac cells: conducting & contractil myocytes |
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Smooth Muscle Tissue |
-Involutary, controlled by autonomic NS -Myofibrils have no regular patter of organization -least metabolic, slow contract, slow fatigue -broad distribution in body -does not form whole organs |
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Smooth muscle tissue contraction |
- intermediate filaments, connected by dense bodies - when actin & myosin filaments slide tension is transmitted to intermediate filaments that pull on dense bodies - cells apear to crinkle when they contract |
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two kinds of smooth muscle |
- single unit or visceral: cells are connected by gap junction, contract as a single unit, found in hollow viscera, walls of small arteries & veins - Multi-unit:consists of individual fibers with own motor terminals, found in iris of eye, walls of large arteries & airways, arrector pili muscles |
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Smooth compared to striated |
- contractions start more slowly & last longer - smooth muscle can shorten & stretch to greater degree - smooth muscle responds to hormones & ANS |
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Skeletal muscle organization (Hierarchy) |
Muscle fascicle muscle fiber myofibril myofilament muscle proteins |
6 |
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Gross anatomy of skeletal muscle |
-Muscle: organ, consists of skeletal muscle tissue & connective tissue, muscle has belly & tendons at each end -Fascicle: bundle of muscle fibers, can be seen with eyes in muscles -Muscle fiber: one muscle cell, can be very short or up to a foot in lenght, multinucleate -Also includes Connective tissue, blood & nerve supply |
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Muscle fiber |
-one muscle cell -can be very short or up to a foot in lenght - multinucleated, nuclei periphery - sarcolemma=plasma membrane -sarcoplasm=cytoplasm -sarcoplasmic reticulum=endoplasmic reticulum, stores calcium |
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Myofibril |
-threadlike structurs (organelles) in muscle cells - visible in light microscope -run parallel to cell axis |
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Myofilaments |
-composed of muscle proteins -Proteins are actin(thin filament) & myosin(thick filament) -Elastic filament=titin -titin anchors thick filaments to Z disc, stabilizing position -also plays role in recovery of resting sarcomere length after a muscle is stretched |
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Sarcomere |
-functional unit of muscle fiber,short segment of myofilaments -thick & thin filaments in myofibrl are organized in repeating units called sarcomeres - smallest functional unit of the muscle fiber -interaction between thick & thin filaments of sarcomeres are responsible for muscle contraction |
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Sarcomere orginization |
-includes Z disc, A bands, I bands, M lines - region from one Z disc to the next -I band= only thin filament -Z disc in middle of one I band -A band= array of thick & thin filaments - H zone= just thick filaments - M line is made of the protein that holds thick filaments and found in the middle of H zone |
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Muscle contraction |
-Sliding-filament mechanism -thick (Myosin) & thin (actin) myofilaments slide past one another - sarcomeres shorten - Z discs become closer -I bands dissapear |
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Muscle Connective Tissue fascia |
-sheet of broad band of fibrous connective tissue deep to skin, around muscles or other organs -superficial fascia: subcutaneous layer, areolar connective tissue w/ adipose -functin of superficial fascia: insulation, fat storage, protection, pathway for AVLN to enter & exit muscles -Deep fascia: dense irregular connective tissue, lines body wall, holds muscles together, separates them into functional groups |
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3 layers of fibrous connective tissue |
Epimysium: dense irregular connective tissue, surrounds whole muscle, connects muscle to facia of other muscles/skin Perimysium: dense irregular connective tissue, surrounds bundles of 10/100 fibers=fascicle Endomysium: areolar connective tissue, surround each muscle fiber, contains capillaries |
EPE |
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Tendon |
- Thick, cable like dense irregular connective tissue structures -connect muscles to bone -aponeuroses: thick flattened sheets - collagen of tendons is continuos with collagen of periosteum -tendons & aponeuroses conduct the force of muscle contraction to bones, |
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Skeletal Muscle blood supply |
-Skeletal muscles are innervated & highly vascularized - contraction requires lots of energy: many mitochondria & capillaries necessary - each muscle fiber is in close contact w/ capillaries in endomysium & axon terminal motor neuron - contact point is called neuromuscular junction |
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Motor Neuron neuromuscular junction |
-site where neuron interfaces with sarcolemma of muscle fiber -consists of axon terminal, synaptic cleft, moter end plate |
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Motor Neurons motor end plate |
-modified region of sarcolemma immediately under the motor axon terminal -ACh is released, AP is initiated on muscle side of synapse to initiate muscle contraction -1 neuron may branch to serve many fibers |
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Motor Unit |
-one motor nueron & all muscle fibers it serves -there are large ( gross control) and small (fine control) motor units |
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Sensory neurons |
-Muscle spindle organs: detect muscle length or passive stretch -Golgi Tendon Organs: detect tendon stretch or muscle contraction -both are sensory receptors, send info to spinal cord, brain |
2 |
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Type of skeletal muscle fibers |
-Vary in color *Red:high myogoblin content, many mitochondria & capillaries *White -Vary in speed of contraction *Slow *Fast twitch |
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Slow oxidative fibers |
-slow to contract -red fibers -use oxidative metabolism -resistant to fatigue |
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Fast oxidative |
-contract fast -pink fibers -use oxidative metabolism |
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Fast glycolytic |
-contract fast -white fibers -glycolysis for ATP(Few mitochondria, little myoglobin)=anaerobic |
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Movement of Muscle |
-collaboration of the following -muscles: contract & provide the effort where the muscle performs the movement -bones: the levers, anchoring points which are what gets moved -Joints: act as fulcrum, which allows movement between two bones, muscles must bridge joints - Connective Tissue: holds other parts together, includes tendon, ligament, joint capsule, periosteum, epimysium -Nerves: gives signal to muscles to contract, via neuromuscular junction |
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Organization of muscles |
-Agonist: prime mover, provides major force for producing a specific movement -antagonist: relaxed when agonist contracts, oposes agonist -synergist: aids in movement, prevents unwanted action -fixators: stabilize origin of agonist |
4 types AASF |
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Muscle attachment to bone |
-Lever systems -dependent on nature of attachement -Muscles attached by tendons to bones which transmit force to bone -Origin:attachment to stationary bone -Insertion:attachment to movable bone |
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Lever systems |
-Fist class: can fovor speed/range of movement, or strenght -Second class: favors strenght -Third class: allows greater speed & ROM |
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Fascicle arrangement |
-parallel: greatest degree of shortening -pennate: greatest strenght -convergent: strength, variable ROM -Circular: close an opening -Small # of long fibers: great ROM, parallel -large # of short fibers: great strenght, pinnate |
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